Tying coerces consumers and therefore is exclusionary to competitors. In the US Microsoft case, the legal rule for assessing technical tying was the rule of reason, while in the European Union and South Korean cases, the legal rule applied against Microsoft’s parallel practices was the...

Professor Louis Kaplow's proposal to abandon market definition in estimating market power has been criticised by a number of scholars. Both the proposal and its criticism were analysed theoretically. The recent Chinese case of Qihoo v. Tencent provides an empirical examination of the proposal...